Gravity conveyer



I Jan, 13, 1925.

C. H. LISTER GRAVITY CONVEYER Filed Aug. 31. 1922 2 Sheetsheet 1 I gwuentoz Cervfilzb'itv;

Z18 6mm,

C. H. LISTER- GRAVITY CONVEYER File A z- '1922 .2 Sheets-Sheet 2 Zhvumfloz an enlarged sertion taken on Patented Jan. 13, 1925.

CHARLES H. LISTER, OF-NORTH ST. PAUL, MINNESOTA.

GRAVITY CONVEYER.

Application filed August 31, 1922.

Tmzz whom it may concern.-

Be it known that 1, CHARLES H. Lisrnn, a citizen of the United States, residing at North St. Paul, in the county of Ramsey and State of Minnesota, have invented new and useful Improvements in Gravity Convcyers, of which the followmg 1s a speclfication.

It is my object to provide a novel and efiicient gravity conveyer for use where it is netessary or desirable to convey merchandise abruptly from a. higher to a lower ele.-. vation.

A further object of my invention is to provide a device of this kind wherein the movemovement of the merchandise down. an

abrupt or steep incline is so regulated that the possibility of breakage or damage is minimized.

A further object of my invention is to provide a device of this kind which is automatic in'operation so that the services of an attendant are unnecessary.

Other objects of my invention will appear and be more fully pointed out in the following specification and claims.

In the accompanying. drawings, which illustrate the best form of my device at present known to me, Figure 1 is aside elevation of my improved conveyer; Fig. 2'is a section taken on the line 2-2 of Fig. 1; Fig. 3 is a detail side elevation of the conveyer; Fig. 4; is a fragmentary plan view of the upper portion of the conveyer, parts of the. rollers being broken away to show mechanism otherwise concealed; Fig. 5 is of Fig. 1; Fig. (3 is a detail elevation of the brake actuating mechanism showing the opposite face of the actuating sprocket from the one shown in Fig. 5; Fig. 7 is a detail perspective view of one of the chain lugs, and Fig. 8 is a detail perspective view of the lower end of the stop bar.

My improved gravity conveyer, as illustrated in the drawings, consists of substantially horizontal sections 10 and 11 of different levels, an incline section 12 which joins the-sertions 10 and 11, and means forcontrolling movement of merchandise (preferably incases or packages) down the incline section 12. The several sections 10, 11 and 12 consist of pairs of side rails 13 and 14 between which are mounted rollers 15, the rails 13 being angle irons arranged with one of their flat outer surfaces downward, and

mounted the line 5-5 7 Serial No. 585,339.

the rails 1% being arranged with a flat outer surface upward. Transverse members 15 hold the rails in parallel relation and said rails are supported by legs 17 and braces 16 and 18.

To control the movement of packages on the section 12 a series of pairs of lugs 19 are positioned in the path of the packages on endless chains 20 which are retarded and stopped at predetermined intervals by the hereinafter described mechanism. The chains 20 are arranged in parallel relation (one adjacent to each sideflrail '14) upon sprocket wheels 21 and which mounted on shafts 23 and 2a. These shafts are journalled in suitable bearings secured to the rails let. The upper runs of the chains 20 are supported and guided by channels 25 which are fastened to the inner surfaces of the rails 14.

Connected to a projecting end of the shaft 23 is a governor 26 (Figs. 1, 2 and This governor is driven by a gear 27 on said shaft 23 which meshes \vith'a pinion 28 on a governor shaft 29. The latter shaft 29 extends axially into a brake drum 30, and a brake shoe 31 is movable radially on the shaft 29 in position to engage the inner periphery of said drum. The shoe is on the end of a. pin 32 which is slidable in a suitable perforation disposed diametrically through said shaft 29. A spring 33 is arranged on the pin 32 to normally withdraw the shoe 31 from contact with the drum 30.

Fastened centrally to the shaft 23 is a small sprocket wheel 34: which drives a chain This chain also passes around a sprocket wheel 36 on a shaft 3?. Suitable journa bearings for the shaft 37 are fastened to the vertical surfaces of a pair of the legs 17. The sprocket wheel 36 is provided with a stop pin 38 and a roller 39 adapted to actuate a brake arm 10 when the wheel 36 is rotated. The arm 40 is bifurcated to straddle the sprocket Bet on the shaft 23 and is pivotally mounted on said shaft by means of bearings 41 which are suitably secured to the bifurcated portions of said arm. The lower end of the arm 40 is provided with an arcuate cam surface 4E2 which is adapted to be engaged by the roller 39 as hereinafter described. Extending obliquely upward from the bearings 4C1 the upper end of the arm 4-0 is provided with means for engaging and stopping rotation are of certain of the rollers on the section 10. This engaging means consists of a substantially horizontal plate 43 upon which is mounted a pair of wedge shaped brake shoes 44 and said plate is resiliently supported by a coiled spring 45. A bolt 46 extends axially through the spring45 to limit movement of said spring and to connect the plate 43 with the arm 40.

In addition to the governor 26 for retarding the chains 20, above described, I alsoprovide means for stopping said chains at predetermined intervals, that is so that one of the lugs 19 is stopped in position to receive a box or package at the head of the incline section 12. This stop mechanism consists of'a downwardly extending bar 47, a lever 48, and means mounted on the lower end of the bar 47 for engaging the stop pin 38 once in each revolution of. the sprocket 36. .The bar 47 which is an angle ron formed integral with the lever 48 is pivotally mounted'at 49 on one of the transverse members 16. A stop plate 50 (Fig. 8) is connected by a hinge 51 to the bar 47 a short distance above the lower end thereof. The stop plate 50 is formed from a short angle iron which is cut away or notched to receive the pin 38 as hereinafter described.

As shown in Fig. 7 the lugs 19 are fastened at right angles to the chain 20 upon triangular projections 20 formed on suitably spaced links in said chain. Each link is formed with a hook 20 on one end which is adapted to receive a cross bar 20 of the adjacent link.

To permit movement of the lever 48 and.

lugs 19-, around the sprockets 21 and 22, anti-friction wheels 52 are substituted for the rollers 15, as illustrated, at points where thero-llers would interfere with the movement of adjacent parts.

Operation.

In operation, assuming the mechanism to be in the position shown in full linesrin Figs. 1 and 5, packages may be delivered at more or less irregular intervals to the section 10 of the conveyor. In this starting position the chains 20, carrying the lugs 19, are held stationary by the pin 38 which is in contact with the stop 50 on the tangential bar 47, the wheel 36 carrying the pin 38 be' Inediately after striking the lever 48 the package is caught by the upper lugs 19' and starts to move down the incline 12. Rapid movement is, however, prevented by the governor 26. Thus, as the package imparts movement to the chains 20 by means of the lugs 19 said chains rotate the shaft 23- carrying the gear 27; The latter gear, by means of the pinion 28, rotates the shaft 29 carrying the brake shoes 31. As the speed tends to increase the brake shoe 31 which is weighted, moves outward under centrifugal force, against the action of thespring 33,and into engagement with the stationary brake drum 30. Frictional contact between the shoe 31 and drum thus retards and prevents excessively rapid movement of the packages down the incline 12.

As soon as the above described movement down the incline starts the roller 39, on the face of the sprocket 36, comes in contact with the cam surface 42 on the brake arm and tiltssaid arm so as to bring the brake shoes 44 into contact with the rollers 15 on the section 10. This, as will be readily understood, prevents rotation of the rollers 15 so that any package subsequently delivered to said section will remain thereon until the rollers are released. However, as soon as the first package has passed down the incline 12 a distance about equal to the distance between the lugs on the chain 20, the brake shoes 44 release the rollers 15 under the action of gravity. This release of the rollers 15 is permitted by movement of the roller 39 out of contact with the cam surface 42 on the brake arm 40. 'By this time a sec ond pair or lugs is in position to receive a package at the head of the incline 12. Re

gardless of whetheror not the second package is delivered to the incline section 12 the movement caused by the mass of the first package under the action of gravity continues until said package is delivered to the substantially horizontal section 11 from whence it is conveyed to the place of stor age or use. I

Packages, carried by the lugs 19, are thus allowed to move down the incline section 12 until the pin 38 again engages the stop plate on the bar 47. 'This will occur as soon as the sprocket 36'has made one revolution because the bar 47, after being moved to its dotted line position by the first package, immediately returns under the action of gravity to position for subsequent engage- When said pin'strikes' ment with the pin 38. the plate 50 the several sprockets, chains and lugs 19 are stopped, onep air of the lugs being in position to receive a package near the head of the incline.

It is obvious, where a long incline is necessary or where a larger number of lugs on the ch'ain 20 are used. that it will be desirable to apply the brake shoes 44 to the rollers 15 for a greater proportion of a cycle or more frequently. This could be accomplished by the use of a plurality of rollers 39 on the sprocket 36 so that the brake shoes let would be caused to alternately engage and release the rollers at any desired frequency. I consider this, and other changes as to the timing of the mechanism, within the scope of my invention.

Having described my invention what I claim as new and desire to protect by Letters Patentis:

1. In a gravity conveyer the combination with a substantially horizontal section adapted to receive packages to be conveyed and a downwardly extending section arranged to receive packages from said horizontal section, and means for automatically stopping packages at predetermined intervals on both of said sections.

2. In a gravity conveyer the combination of a substantially horizontal section ad'apted to receive packages to be conveyed, a downwardly extending section arrangedto receive packages from said horizontal section, means for retarding s'aid packages during their movement on said downwardly ex tending section, means for stopping packages on said substantially horizontal section, and synchronized means actuated by the packages on said downwardly extending section for alternately stopping and releasing said retarding means.

3. In a gravity conveyer the combination of a substantially horizontal section adapted to receive packages to be conveyed, a downwardly extending section arranged to receive packages from said substantially horizontal section, endless chains adapted to retard said packages during their movement on said downwardly extending section, means for stopping said chains at predetermined intervals, and means actuated by packages on said downwardly extending section for releasing said chains.

l. In a gravity conveyer a pair of side rails arranged in a steep incline, means mounted between said rails for supporting packages thereon, an endless chain mounted between said rails, means projecting from said chain for engaging packages, a governor operatively connected with said chain whereby downward movement of packages is retarded, and means for stopping said chain at predetermined intervals comprising a wheel operatively connected with said chain, a pin projecting from said wheel, and abar tiltably supported so as to project into the path of packages at one end and to intermittently engage said pin at its other end.

5. In a gravity conveyer arranged at a steep incline means mounted on said conveyer for supporting packages thereon, an endless chain mounted in said conveyer, means projecting from said chain for engaging packages, a governor operatively connected with said chain whereby downward movement of packages is retarded, a bar tiltably supported so as to project into the path of packages, a stop on said bar, and means operatively connected to said chain and arranged to intermittently engage said stop.

6. In a gravity conveyer a substantially horizontal section and a steeply inclined section extending downward from said horizontal section, means mounted on both sections for supporting packages thereon, an endless chain mounted in said inclined section, means projecting from said chain for engaging packages, a governor operatively connected with said chain whereby downward movement of packages is retarded, an arm tiltably mounted beneath said sections, means mounted on said arm for stopping packages on said horizontal section, and means operatively connected with said chain for actuating said arm to stop packages at predetermined intervals.

7. In a gravity conveyer a substantially horizontal section and a steeply inclined section extending downward from said horizontal section, means mounted on both sections for supporting packages thereon, an endless chain mounted in said inclined section, means projecting from said chain for engaging packages, a governor operatively connected with said chain whereby downward movement of packages is retarded, means for intermittently stopping said chain and synchronized means for intermittently stopping packages on said substantially horizontal section, comprising an arm tiltably mounted beneath said sections, means mounted on one end of said arm for stopping packages on said horizontal section, and means operatively connected with said chain for actuating said arm at predetermined intervals.

In testimony whereof, I have hereunto signed my name. to this specification.

CHARLES H. LISTER. 

